In recent years, resistance change type memories (resistive RAMs (ReRAMs)) attract attention as a nonvolatile memory capable of rewriting data at a higher speed as compared with a NAND flash memory or the like. As a characteristic of a memory device using a ReRAM, reading from the memory device is very fast, and reading can be performed with a constant delay time after issuance of a read command (for example, see Patent Document 1). On the other hand, writing in the memory device takes more delay time than that of reading. Moreover, the delay time is not constant. This is because checking whether writing has been performed normally and rewriting a bit that has not been written normally are automatically performed within the memory device. The delay time becomes short if the writing is performed normally at one time, and the delay time becomes longer if rewriting is performed. In a memory device having such characteristics, using a control method such as referring to a signal indicating the state of the memory device after transmitting a write command and transmitting a next command after receiving a status signal indicating completion of writing (for example, see Patent Document 2).